Volcano Formation

Very large volcanoes that form due to increased pressure and magma build up over time and that have had an eruption with a VEI (Volcanic Explosivity Index) of 8 are classified as:

• Hot spots

• Normal volcanoes

• Supervolcanoes

• All types of volcanoes

Answer explanation

Supervolcanoes are defined as very large volcanoes that can produce eruptions with a VEI of 8. They form from significant magma buildup and pressure over time, distinguishing them from other types of volcanoes.

The Hawaiian Islands formed over a ________, which is a relatively fixed location in the mantle where the magma is much ________ than the surrounding magma. Which terms best complete the sentences?

• convergent boundary; colder

• hot spot; hotter

• divergent boundary; hotter

• reverse fault; colder

Answer explanation

The Hawaiian Islands formed over a hot spot, which is a fixed mantle location where magma is hotter than the surrounding magma, allowing it to rise and create volcanic islands.

Tags

NGSS.HS-ESS2-3

What is a key difference between a volcano that forms above a hot spot and one that forms at a subduction boundary?

• Hot spot volcanoes form at plate boundaries.

• Subduction boundary volcanoes form in the middle of a plate.

• Hot spot volcanoes form over a mantle plume.

• Subduction boundary volcanoes form far from plate boundaries.

Answer explanation

Hot spot volcanoes form over a mantle plume, which is a stationary source of magma beneath the Earth's crust. In contrast, subduction boundary volcanoes form at the edges of tectonic plates where one plate is forced under another.

Where do hot spot volcanoes generally form?

• At convergent plate boundaries

• In the middle of a plate

• Along the subduction zone

• At divergent plate boundaries

Answer explanation

Hot spot volcanoes typically form in the middle of tectonic plates, away from plate boundaries. They arise from mantle plumes that create volcanic activity, unlike those at convergent or divergent boundaries.

What causes the formation of most other volcanoes besides hot spot volcanoes?

• Erosion of the crust

• Subduction zone friction

• Mantle plumes

• Ocean currents

Answer explanation

Most volcanoes form due to subduction zone friction, where one tectonic plate is forced under another, causing melting and magma formation. This process is responsible for the majority of volcanic activity, unlike hot spot volcanoes.

Tags

NGSS.HS-ESS2-3

What is the role of friction in the formation of subduction boundary volcanoes?

• It cools the magma.

• It melts the crust into magma.

• It creates ocean currents.

• It forms mantle plumes.

Answer explanation

Friction at subduction boundaries generates heat, causing the oceanic crust to melt into magma. This process is crucial for the formation of subduction boundary volcanoes, making 'It melts the crust into magma' the correct choice.

What is the primary cause of magma formation at subduction zones?

• Ocean currents

• Friction melting the crust

• Mantle plumes

• Erosion

Answer explanation

The primary cause of magma formation at subduction zones is friction melting the crust. As one tectonic plate is forced under another, the intense pressure and heat cause the crust to melt, forming magma.

Tags

NGSS.HS-ESS1-5

NGSS.HS-ESS2-1

What is the main feature of a subduction boundary?

• Mantle plume

• Ocean trench

• Hot spot

• Mid-ocean ridge

Answer explanation

The main feature of a subduction boundary is the ocean trench, which forms as one tectonic plate is forced under another, creating deep underwater valleys.

Tags

NGSS.HS-ESS1-5

NGSS.HS-ESS2-1

Which oceanic plate is mentioned in the context of the "Ring of Fire"?

• Atlantic Plate

• Pacific Plate

• Indian Plate

• Arctic Plate

Answer explanation

The "Ring of Fire" is a major area in the Pacific Ocean where many earthquakes and volcanic eruptions occur. The Pacific Plate is the largest tectonic plate in this region, making it the correct answer.

Tags

NGSS.HS-ESS1-5

What happens when an oceanic plate collides with a continental plate?

• The oceanic plate rises above the continental plate

• The oceanic plate subducts beneath the continental plate

• The plates move apart

• The plates remain stationary

Answer explanation

When an oceanic plate collides with a continental plate, the denser oceanic plate subducts beneath the lighter continental plate, leading to geological features like trenches and volcanic activity.

Tags

NGSS.MS-ESS2-2

NGSS.MS-ESS2-3